Improvement in key-hole covers



e. W. AMBoRN. KEY-HOLE COVERS.,

Nof. 194,535.. r Patented Aug, 28,1877,l

vENToR,

,zwm/M/ y i C ATTORNEY'S.

UNITED S'LA'IEs PATENT -OEEICE GEORGE W. AMBORN, OF PEABODY, KANSAS.-

Specification forming part o'f Letters Patent No. [94,635gdate'd August 28, 1877i; A application filed February 17, 1877.

To all whom yif may concern:

Be it known that I, GEORGE W. AMBoRN, of Peabody, in the county of Marion and State of Kansas, have invented a new and valuable Improvement in Key-Hole Uoverer; and I do hereby declare that .the following is a full, clear, and exact description of the construction and operation of the same, reference being had to the annexed drawings, making a part of this speciication, and to the letters and figures of reference marked thereon.

Figure l of the drawings is a representation of the interior of a lock with the cover-plate removed. Fig. 2 is an under-side view ot" the cover-plate. and Figs. 3 and 4 are detail views.

The object of this invention is to provide convenient means for closing a key-hole so as to prevent a lock from being opened. This object l effect chiefly by the employment of' a keyhole-closing slide, in combination with a tumbler, an operating-key, and a catch for locking said key, substantially as hereinafter set forth.

In the accompanying drawings, A designates one plate ot' an ordinary lock-casing, and theside pieces rigidly secured thereto, and B the cover-plate thereof. C, Fig. 1, designates an ordinary latch-bolt, operated in the usual manner by arms d d on a hub, D, which has a prismatic aperture adapted to receive a door-knob spindle. There is also a latchspring, E.

All of the above devices work in the part A of said casing. So, also, does lock bolt F, which is longitudinally slotted, and slides over guide-stud or guideblock f, formed on the inside of said plate A. Said bolt F is provided on its rear end with a nearly-triangular piece, F1, (formed as shown in Fig. 1,)`

and with a nearly-triangular recess, F2, in its under side.

On the top of the rear extension of the bolt F is a lug or block,f.

G -designates a tumbler, pivoted by its rear end to plate A, and held downward by its gravity and by the pressure of a spring, G. Said tumbler is provided with a projection, g, which is adapted to set ,either in front of block or lug f', or behind the same, thereby locking bolt F either in an extended or retracted position, as desired. The lower side of said tumbler extends below the upper part of recess F?.

When the key is inserted through key-hole H and turned, it raises said tumbler, and operates bolt Fin the usual manner, so as Ato shoot or withdraw said bolt, according to the direction of said turning.

But my invention principally consists in the i following means for closing said key-hole, so as to prevent the ingress of the key: I designates a slide, working between guide-blocks I I on the inner face of the plate B, so as to close or to open said key-hole, according as it is advanced or withdrawn. Said slide is longitudinally slotted at fi, so as to move over the guide-pin stud fil, whereby it is secured to the inside ot said plate B.

A stop-block, J, prevents slide I from being moved too far beyond the key-hole. The said slide is provided with a recess, K, in its under side, near its rear end, which recess is in the form of a triangle, having its base downward, and a small upward rectangular extension, la, on its vertex. On the upper side of said bolt, near its rear end, is formed a small block, k', similar to lug f', and adapted to be engaged by a projection, l, (similar to projection g,) formed upon a tumbler, L, which tumbler is depressed by a spring, L'. The rear upper end ot'v said spring is set into a stud, Z1, and the middle of said spring has its bearing against a curved block, l2, so as to have arolling and nearly frictionless contact therewith, though braced thereby. Said tumbler, when in its normal position, extends below the upper part of recess K, and rests upon a small xed stop, 13. Said tumbler is raised and said slide l moved forward or backward by means of a keyM. `(Shown in detail in Fig. 3.) Said key is journaled in said platesA and B, and one end of its shank extends through an opening m, in said plate D. This latter end is adapted to receive outside of said plate a thumb-piece or head, N. Said th umh-piece or head is notched at n, to receive the point of a small dog or catch, 0, which is pivoted to the exterior of the cover-plate B. By means of this dog or catch O the withdrawal of the said slide from the said key-hole is rendered impossible from the outside.

Slide I is recessed at i2 on its front end, and

block J is correspondingly recessed at j, as indicated by dotted lines in Fig. 2, so that when said slide is shot across said key-hole it engages with said block, and is braced thereby. This prevents it from being displaced by any inward push.

What I claim as new, and desire to secure by Letters Patent, 1s-

The slide I, having the slot i, triangular recess K, with rectangular extension k, block k', and recess i2, in combination with the cover B, provided on its under face with the stop-block J, recessed at j, guide-blocks II I', arranged above and below the key-hole studs il l' lz l, spring L', and the pivoted tumbler L, having lug l, said devices being independent of the locking mechanism, and operated by an independent key, substantially as and for the purpose set forth.

In testimony that I claim the above I have hereunto subscribed my name in the presence of two witnesses. y

GEORGE W. AMBORN. Witnesses: i f

A. B. SALISBURY, JNO. J. FUNK. 

